There are numerous previous disclosures relating to portable clamps on which additional clamps or rods can be mounted, and disclosures disclosing wedge slot devices wherein a V-shaped slot catches a rope or cord when properly positioned are well known, but none are equivalent to the present disclosure.
U.S. Pat. No. 994,630 discloses a pin loosely connecting two clamp frames together. U.S. Pat. No. 1,352,647 discloses a hinge mechanism for pivotally connecting two clamp frames together. U.S. Pat. No. 4,141,542 discloses a C-clamp with one leg adapted as a guiding ledge to which a second C-clamp is connected.
U.S. Pat. No. 1,410,184 discloses a spring-loaded locking mechanism fastened between two C-clamp frames.
U.S. Pat. No. 2,606,583 discloses C-clamp frames with tongue and groove interconnecting means. U.S. Pat. No. 2,636,527 discloses C-clamp frames with male and female interconnecting elements. U.S. Pat. No. 2,778,939 discloses a pair of interfitted C-clamp frames.
U.S. Pat. No. 2,669,958 discloses a welder's work holder appliance where C-clamp frames are connected to each other using ball joints.
U.S. Pat. No. 5,405,124 discloses a C-clamp with auxiliary connecting elements used to connect two clamp frames together. U.S. Pat. No. 4,607,829 discloses C-clamp frames with spaced holes allowing fasteners to secure juxtaposed clamp frames.
U.S. Pat. No. 5,765,822 discloses a C-clamp frame with a clamping module connected through frictional contact between dowel pieces.
U.S. Pat. No. 4,825,513 discloses C-clamp frames modularly connectable along a linear pathway.
U.S. Pat. No. 4,969,636 discloses C-clamp formed with an opening through which a shaft extends and means for locking the shaft to the clamp. U.S. Pat. No. 4,500,077 discloses a C-clamp with a pivoting hinge element used to connect a clamp frame to a rod.
U.S. Pat. No. 3,574,900 discloses a jamming cleat, but unlike the present disclosure it is not integrally formed as part of a C-clamp frame.
U.S. Pat. No. 1,369,747 discloses C-clamp frames with apertures through which flexible seat suspenders are attached. U.S. Pat. No. 2,907,630 discloses a C-clamp with a flexible clamping element.
U.S. Pat. No. 4,828,210 discloses a C-clamp with integrated bore and angled cross cam slot for locking a tether line.
U.S. Pat. No. 6,663,094 discloses an apparatus for holding a ski during repair and maintenance with an intermediate tensioning device comprising a C-clamp, accessory cord and cleat component.